Circuit-breaking device for reciprocating electric machines



(No Model.)

0. H. RICHARDSON. CIRCUIT BREAKING DEVICE FOR RECIPROCATING ELECTRICMACHINES.

No. 508,050. Patented Nov. 7, 1893.

INVENTOR WITNESSES:

IIIM

6% 7f, Man-X10014. FIG. 5.- Q

if. 04.7mm

UNITED STATES PATENT OFFICE.

CHARLES H. RICHARDSON, OF PHILADELPHIA, PENNSYLVANIA.

CIRCUIT-BREAKING DEVICE FOR RECIPROCATING ELECTRIC MACHINES.

SPECIFICATION forming part of Letters Patent N 0. 508,050, datedNovember '7, 1893.

Application filed July 2, 1892. Serial No. 488,749. (No model.)

To all whom it may concern:

Be it known that 1, CHARLES H. RICHARD- SON, a citizen of the UnitedStates, and a resident of the city and county of Philadelphia and Stateof Pennsylvania, have invented certain new and useful Improvements inCircuit- Breaking Devices for Reciprocating Electri calMachines, ofwhich the followingis a specification.

My invention relates to improvements in circuit breaking devices forreciprocating electromagnetic machines and the object of my invention isto furnish an adjustable circuit breaking device, by means of which thestroke of the armature of an electro-magnetic machine, for instance ofan electric dental plugging instrument, or an electric bell, may beVaried at will, the extreme length of stroke being limited only by thestrength or attractive force of the electro magnets.

In my circuit breaker both contact points are carried by thereciprocating part of the electric machine, which is generally thearmature, one of these contact points being preferably a screw which isinsulated from the armature and which can be moved in or out forpurposes of adjustment, and the other contact consists of a spring orlever, one end of which is secured to the armature and the other end ofwhich is free and is weighted, as hereinafter described. In connectionwith the armature are adjustable stops which limit its movement ineither direction; the armature is also furnished with the usual devices,generally springs, for lifting it from the electro magnets when thecircuit is broken.

In the accompanying drawings forming, part of this specification, and inwhich similar letters of reference indicate similar parts throughout theseveral views-Figure 1, is a side elevation of an electric dentalplugging instrument fitted with my improved circuit breaker; Fig. 2, anend elevation of the upper part of the same; Fig. 3, a side elevationofan electric bell furnished with my invention; Fig. 4., my invention asapplied to a solenoid magnet, andFig. 5, a side View of an armature,showing the lower contact point arranged as a'lever.

A. are the electro magnets, B. the armature pivoted at O.

D. is a spring or lever, one end of which is secured to armature B. atE. and the other end of which is free and carries a weight F.

G. is the upper contact point, consisting preferably of a screw andwhich is carried by an insulated bracket H. carried by the armature B.

I. J. are stops for limiting the movement of the armature B. In Figs.land 2, the upper stop 1. consists of an adjustable threaded bar L.,moved either up or down as may be desired by meansof a stationary nutM., while the lower stop J. consists of the head of the anvil of theplugging instrument. In Fig. 3, both upper and lower stops I. J. consistof screws carried by brackets N. carried by the frameO. of the device.

One Wire from the battery or other source of electric supply isconnected to the contact point G.; the other wire to the electro magnetsA. and from these magnets to the spring or lever D.

The operation of the device is as follows: The screw G. and spring D.being in contact the circuit is closed, the magnets A. are en ergizedand attract the armature B. rapidly until it is suddenly'arrested in itsmovement by coming in contact with the stop J.; when this happensthemomentum acquired by the spring or lever D. causes the weighted or freeend of this spring or lever to fly downward or away from the uppercontact point G. breaking the current and demagnetizing the mag nets A.The spring P. immediately raises the armature from the magnets A. andbefore the spring D. again makes contact with theupper contact point G.the armature has reached its highest point, as determined by the upperstop I. It will be observed that during the downward movement of thearmature B. the contact point G. and the spring D. are in contact untilthe armature has reached the end of its stroke, as determined by thelower stop J., and during all this time the magnets are energized andattracting the armature, the circuit not being broken until the jarcaused by the armature striking the lower stop moves the spring D. outof contact with contact point G. This feature is particularly desirablein connection with the break apparatus of Ruhmkorff coils and otherinduction apparatus, as it allows the core to be fully magnetized beforethe circuit is broken.

As the contact points are both carried by and move with the armature itwill be seen that the stroke of the armature is only limited by thepower of the magnets and that the current will always have time to fullyenergize them before being broken, and it will be further seen that bymeans of the stops I. J. the stroke of the armature may be adjusted asdesired, a feature which is very important in many cases andparticularly so in dental pluggers, where sometimes a heavy blow isrequired and at others alight one. ing the stroke of the armature a blowof any force within the power of the magnets may beimparted to theplugging tool R.--Fig. 1. In Fig. 3 S. is a hammer carried byor at theend of the armature and T. a gong I'nFig. 4;; my circuit breaker isshown as applied to a solenoid magnet. A-. is the spool of the magnet,B. the core, D. a light spring carried by the core, and G. a contactpoint carried by a rod Cb projecting outward from the core and insulatedfrom this rod. I. is the-ripper stop, J. the lower stop limiting themovements of the core,- P. a spring for raising core when current isbroken, and b. a confact poin't ca-rried by upper end of springl). Onewire-from source of electricalsupplypasses to spool A. and thence'tospring D. r The other wire is connected to upper contact piece G, Thenormal position of the contact points G. b. is together, but when thecore B. is drawn into the spool A. and is suddenly arrested in itsmovement by the lower stop J. the jar causes the contact piece 1).,carried by spring 1)., to be moved away from contact (3 breaking thecircuihwhen the spring P, asserts itself and raises the core to itshighest position, when the recoil of spring D. againthrows contact 1).against contact G. rte-establishing the circuit when the core is againdrawn into the spool. WViththis form of brake apparatus thefull strokeof the core of a so- By varylenoid may be obtained, which is impossiblewith the ordinary brakepiece.

In Fig. 5 the movable contact piece is shown as a lever supported upon astandard 0 carried by the armature B. A light spring d, bearing againstthe armature and the contact piece raises this latter into contact withthe fixed contact G after the movable contact piece has lost itsmomentum.

Having thus described my invention, I claim- V 1. The herein describedcircuit breaker for reciprocating electro magnetic devices, consistingof a rigid and a movable contact piece, carried by the reciprocatingpart of the mcchanism and operating to break the electric'circuit on thecompletion of t e rrraerive stroke and make it on the completion of therelease strategy the movement due to the moinentu'm of the movablecontact, substantially described. I

21 The combination in a circuit breaker of an electro' magnet ormagnets, an armature, devices for raising said armature from saidmagnet. when current is bro'ken, a movable and a rigid contact pointca'tiied' by said armaturean'd-one or both of which are insulated fromsaid armature, an adjustable stop for limiting the upward movementofsmarmatu-re and afixed or movable stop for" liniiting its downwarmovement.

3. The combination in a cit-cult breakers! a magnet and; an armature, arig idcontact point carried by and insuiaterrn-om said armature,- amovable contact point carried by said armature, and the f r'e'eorc'ontact end of which is weighted, and-a uiov able stop, by means ofwhich the stroke of said armature maybe adjusted.

CHARLES H. RICHARDSON. Witnesses: r

MoRRis' R. B o'o'KI'Us, CHAS. A. BUTTER.

